chad500sl

My 2021 E350 has started showing a message on the dash to check the rear right turn signal. When the signal is on, I get the message and the click sound is faster. Outside the car, all is well. All blinkers work exactly correctly. I expect the current monitor for the light is a little too sensitive. It happened a month ago and went away the next drive. This time the error seems to be sticking around.

Is there a software update or something to fix this fault? I hate to take it to the deal for something so trivial. I've had the car for about 3 months and have a CPO warranty.

konigstiger

Get it checked under warranty.

joe72camel

Happened to me on my 6 months old car, had the exact same symptoms.
Brought it in the first time to the dealer and was fixed for about a week. Brought it in again and they did a throughout check on the harnesses, nonetheless they decided to change the tail light assembly.. Fault went away after the 2nd time i brought it in.
They had to order it and was changed during my Service A.

chad500sl

Following up, the car went in for A service and MB replaced the problematic light under warrantee with no fuss. MB also updated the software on the surround cameras as they cut out once in a while. Kudos to Mercedes of Jacksonville for handling these items pleasantly. Time will tell if the issues are truly fixed, I'm optimistic!

DKNYC

Same thing happened to me, i opened the felt compartment where the light is, just moved the wire to the bulb a bit and made sure the rubber grommet was in place securely where it connects to the rear light housing, since then havent seen the error. I think its because the wire is so close to the actual felt covering and if you put something in the compartment in the trunk that touches the felt it could move the wire a bit and trip the error. I also just duct taped the wire to the frame so it wouldnt rest directly on the lining, put back the cover and since then no error. Also note this was when the warning to check the right rear bulb and the actual turn signal was functioning properly when i checked the turn signal outside of the care.. Assume if the turn signal was not functioning outside the car, the above fix would not work.

Merc93

Currently going through the same issue, happened out of nowhere. I did move around the grommit like you. Turned the car off turned it back on. The signal blinked slowly for 2 seconds then went back to blinking fast. All outside is fine

DKNYC

how long has it been going on, mine went away after a week or so, i believe the system resets itself every so often, if you made sure the harness was secure and the wire was not moving around, after 2 weeks or so bring it to the dealer. Is the bulb actually out btw and does the turn signal outside the car function normally?

Merc93

It just started to happen last night. Outside the car works fine. I did not see any issue with the wire and grommet.

DKNYC

See if it goes away after a week or so, if you dont see an issue with harness or grommet and bulb turn signal operates normally outside the car, once system resets should clear. If it doesn't have dealer look at it. Only other thing would be if water got in the rear tail light, you would see condensation or a Crack though. Give it a week or so and if still there make appointment.

DKNYC

BTW mine started again yesterday, i'm just going to the dealer and let them deal with it, the car was 75k and still under warranty

Merc93

Mine doesn't do it for a day, then does the next day. Off and on. As your one is under warranty ill wait to see what they did to yours